The PHOTOLAV can be set into any of the Deville printing trays (starting at 30x40cm) and does two things. First it drives the wash water at high speeds in to the tray, and secondly it pushes the fixerout from the bottom of the tray so that the paper is more thoroughly washed. The PHOTOLAV just needs to be attached to the photo tray to easily turn it in to a washer.